And danbury



(No Model.) M. C. JOHN SON.

DRIVING QLUTCH- No. 527,064. I Patented 0011.9.1894.

UNITED STATES MOSES C. JOHNSON, OF HARTFORD, CONNECTICUT, ASSIGNOR TOTHE T. 85 B.-

PATENT QFFICE.

TOOL COMPANY, OF PORTLAND, MAINE, AND DANBURY, CONNECTICUT.

DRIVING-CLUTCH.

SPECIFICATION forming part of Letters Patent No. 527,064, dated October9,1894.

Application filed January 20, 1894. Serial No- 497|4=93. (No model-l Toall whom it may concern:

Be it known that I, MOSES C. JOHNSON, a citizen of the United States,residing at Hartford, in the county of Hartford and State ofConnecticut, have invented certain new and useful Improvements inDriving-Clutches, of which the following is a specification.

The invention relates to the class of clutches that are adapted to beconnected with the live spindle of a lathe or the equivalent part of asimilar machine for centering and holding the blank to be operated upon,and the object is to provide a simple'and cheap device of this classhavingpositive centering and clutching means that will quickly grasp andfirmly hold the blank so that it will be correctly rotated with thespindle, whereby the work can be easily and quickly placed in andremoved from position in the machine, or replaced in the same positionafter removal, as often as desired.

Referring to the accompanying drawings: Figure 1 is a side view of oneform of clutch. Fig. 2 is a view of the face of the same. Fig. 3 is acentral section, illustrating its use in connection with the end of adrill. Fig. 4 is a side view of a modified form of the clutch. Fig. 5 isa face view of this latter form. Fig. 6 is a central section of thesame, showing the shank of a drill engaged by the clutch. Fig. 7 is adetail view of the driving finger; and Fig. 8 is a view of the end ofthe drill shank shown in Fig. 3.

The body of the clutch is usually turned to shape from steel, with ashank, 1, adapted to engage the driving spindle of a lathe or similarmachine, and a head, 2, that has the centering and clutching parts. Thisclutch is more particularly adapted and intended for use in connectionwith the turning of drill blanks and when it is to be used for clutchingthe squared end of such a blank the head is preferably provided with amale centering part, which consists of a small projecting cone, 3, thatis adapted to fit into the female centering socket, 4., or indentationmade in the end of the shank, 5, as shown in view 3.

In a socket or chamber, 6, in the face of the head on one side of thecenter is placed a grasping plunger or finger, 7 that is normally thrustoutward by means of a spring, 8; a

small pin, 9, working in a slot being provided to prevent the completeremoval of the finger from its chamber. The front side of the outer orprojecting end of this finger is provided with a flat surface, while theback edge is usually rounded oi, as shown in Fig. 7, and in the end ofthe blank to be operated upon, as far from the axis as the finger oftheclutch head is from the centering cone, a recess, 10, is milled withone flat wall for the engagement of the fiat face of the finger.

When the clutch is placed in engagement with the live spindle of amachine anda blank provided with a centering indentation and fingerrecess, as shown in Figs. 3 and 8, is forced up against the face of theclutch, the centering parts fit together while the finger is forced backagainst the spring in its chamber by the end of the blank until theclutch rotates, or the blank is rotated, and the finger comes around toits recess and then springs forward into it so as to catch against orgrasp the flat wall of the recess and drive the blank forward with it.

If the clutch is to be used with a blank having a tapering end, as isthe case with small twist drills, the head instead of being providedwith a projecting cone, has a conical female recess, 11, into whichextends the tapering end, 12, of the blank to be clutched, as shown inFig. 6; and when the device is to be used for rotating blanks of smalldiamlater, of course, the head may be reduced, as

shown in Fig. 4, and the clutching finger located near the axis. Bymeans of this construction, a blank or piece to be turned can be quicklymade to engage the clutch by fitting the conical centering partstogether and then turning either the clutch or the blank until thefinger springs outward and grasps the walls of its recess in the end ofthe blank.

The clutch is cheaply formed with either a male or a female conical partfor centering the blank and the grasping finger very securely engagesits recess, so as to firmly revolve the blank, which can be as quicklyremoved as placed in position to be operated upon. This constructionalso permits a blank once centered to be removed and inspected orsubjected to other operations and then quickly returned to the grasp ofthe clutch without any careful manipulation to obtain and insure theoriginal centers, so that it can be further turned on the same centers,if desired.

I claim as my invention- As a new article of manufacture, a tool havinga shank and a head with a fixed conical center on the axis of the tool,said head being smaller in diameter than the part it is to engage whenin use, and a spring plunger pro- 1 o jecting from the face of the headon one side of the axis of the tool for engaging a bearing on the end ofthe part to be rotated, substantially as specified.

MOSES O. JOHNSON.

Witnesses:

EDMUND TWEEDY, CHARLES H. WILCOX, J r.

